A comparative LCA of rice straw utilization for fuels and fertilizer in Thailand

Life cycle assessment of four rice straw utilization systems including; (1) direct combustion for electricity, (2) biochemical conversion to bio-ethanol and biogas, (3) thermo-chemical conversion to bio-DME, and (4) incorporation into the soil as fertilizer have been conducted to compare their environmental performances. The results showed that per ton of dry rice straw, the bio-ethanol pathway resulted in the highest environmental sustainability with regards to reductions in global warming and resource depletion potentials. Rice straw bio-DME was preferable vis-à-vis reduction in acidification potential. Rice straw electricity and fertilizer also brought about several environmental benefits. The key environmental benefit of rice straw utilization came from avoiding the deleterious effects from burning straw in situ in the field. Recommendations for enhancing environmental sustainability of rice straw utilization for fuels and fertilizer are provided.